172 SNAKES OF CEYLON. 



rectiform, the 3rd to 7th from the ventrals slightly oblique. 

 Vertebrate, where the rows are odd, slightly enlarged. Last 

 two rows enlarged. Ventrals : Obtusely angulate laterally. 

 Anal: Divided. Supracaudals : In even rows. Subcaudals : 

 Divided. 



Dentition. — Maxillary : Syncranterian, anododont, cory- 

 phodont. Palatine : Anododont, feebly kumatodont. Ptery- 

 goid : Anododont, isodont. Mandibular : Anododont, feebly 

 kumatodont. 



Distribution. — South Eastern Asia. 



There are seven species, one of which, viz., mucosus, occurs 

 in Ceylon. 



Zaocys* mucosus Linne. 

 (Latin " mucosus " slimy.) 

 The Dhaman,~\ or Common Ratsnake. 



Tamil : " saray pambu " (straight snake). The natives 

 say it takes a direct bee-line from danger. 



Sinhalese : " garandiya " (Willey). 



Synonymy. — Coluber mucosus, C. dhumna, C. blumenbachii, 

 Natrix mucosa, Cory phodon blumenbachii, Leptophis trifrenatus, 

 Ptyas mucosus. 



History. — First brought to notice, and christened by Linne 

 in 1766. Russell figured it inhis first volume (Plate XXXIV.) 

 in 1796, and again in his second volume (Plate XVIII.) in 1801. 



General Characters. — A formidable snake, growing to over 

 eight feet in length. Head rather long. Snout longish, 

 canthus obtuse, somewhat narrowly rounded. Eye large. 

 Nostril large, occupying the whole depth of the . suture 

 between the nasals. Neck distinctly constricted. Body 



* This snake was placed by Boulenger in the Genus Zamenis. Some 

 time ago I pointed out that its affinities are closer to Zaocys than 

 Zamenis. In all the species of Zaocys the costal rows are in even 

 numbers, and in the species I have examined there is an absorption of 

 the vertebral row in the neck, into the uppermost row on the left side. 

 In mucosus precisely the same absorption occurs, but behind midbody 

 instead of in the neck, and the rows then are even in number. Boulen- 

 ger says of the maxillary dentition that in Zaocys the teeth number 20-33 

 and in Zamenis 12 to 20. In the six skulls of mucosus in my collection 

 the maxillary teeth vary from 20 to 24, so that in this important 

 character also the species conforms more to the dentition cf a Zaocys 

 than to a Zamenis. 



t " Dhaman " is the Sanskrit word for rope. 



